The Fbxw7/hCdc4 tumor suppressor in human cancer.

Fbxw7/hCdc4 is a member of the F-box family of proteins, which function as interchangeable substrate recognition components of the SCF ubiquitin ligases. SCF(Fbxw7/hCdc4) targets several important oncoproteins including c-Myc, c-Jun, cyclin E1, and Notch, for ubiquitin-dependent proteolysis. Recent studies have shown that FBXW7/hCDC4 is mutated in a variety of human tumor types, suggesting that it is a general tumor suppressor in human cancer. Alteration of Fbxw7/hCdc4 function is linked to defects in differentiation, cellular proliferation, and genetic instability. In this review, we summarize what is known about Fbxw7/hCdc4-mediated degradation in the regulation of cellular proliferation and discuss how alteration of its function contributes to human tumorigenesis.